<h3>
Answer: 280</h3>
Work Shown:
x = number of students in the 6th grade class
30% = 30/100 = 0.30
30% of x = 0.30x this is equal to 84 since "30% of the 6th graders are boys (and there are 84 boys in sixth grade)", so we say 0.30x = 84
Divide both sides by 0.30 to isolate x
0.30x = 84
0.30x/0.30 = 84/0.30
x = 280
So there are 280 students overall in the 6th grade class.
The answer is B. an = 13 + 14(n-1)
Yes because 4x3^x =12^x since the coefficient is added to the answer because it is in the 3.
Answer:
5.2 x 
Step-by-step explanation:
The $378.49 was earned on the investment if the principal amount of $3000 is invested for 3 years at 4% compounded semi-annually.
<h3>What is compound interest?</h3>
It is defined as the interest on the principal value or deposit and the interest which is gained on the principal value in the previous year.
We can calculate the compound interest using the below formula:

Where A = Final amount
P = Principal amount
r = annual rate of interest
n = how many times interest is compounded per year
t = How long the money is deposited or borrowed (in years)
Here,
P = $3000
r = 4% = 0.04
n = 2
t = 3 years
After plugging all the values in the formula:

After solving:
A = $3,378.49
I = A - P = 3,378.49 - 3000 = $378.49
Thus, the $378.49 was earned on the investment if the principal amount of $3000 is invested for 3 years at 4% compounded semi-annually.
Learn more about the compound interest here:
brainly.com/question/26457073
#SPJ1